With the advent of the Internet, society has witnessed the expansion of a global packet-switched network into an ever increasing number of homes and businesses. This has enabled an ever-increasing number of users to communicate with each other, primarily utilizing electronic communications such as e-mail and instant messaging. Meanwhile, advances have been made in delivering voice communication over packet-switched networks, driven primarily by the cost advantage of placing long-distance calls over the packet-switched networks, but also by the ability to deliver advanced service features to the customers. This cost advantage can be enjoyed by both a service provider delivering the voice communication over packet-switched network service (in a form of lower operating cost), as well as a customer who subscribes to the services of such a service provider (in a form of lower service subscription fees). Technology dealing with the delivery of real-time voice communication over the packet-switched network is generally referred to as voice-over-packet, voice-over-IP or VoIP.
As far as a communication endpoint in a VoIP system is concerned, several implementations have been envisioned in the industry. Some service providers have offered its customers the use of a VoIP phone that is connected directly to the packet-switched network. Even though these VoIP phones can offer a number of advanced communication features, deployment of VoIP phones obviously leads to an increased cost associated with purchase of a new VoIP phone. Other service providers have offered its customers the use of a so-called “soft phone” or, in other words, a computing apparatus equipped with software to originate and receive calls via the packet-switched network. Yet others have offered their customers the possibility to re-use their existing Plain Old Telephone System (POTS) phones by equipping them with an Analogue Telephone Adaptor (ATA) which essentially mediates communication between the packet-switched network and the POTS phone by translating digital communication into analogue communication and vice versa.
As is well appreciated in the art, the delivery technology for VoIP is fundamentally different from the delivery technology for the traditional PSTN-based calls. As a result of these differences, one area where service providers of VoIP services have encountered challenges is in the area of provisioning of emergency services. Several solutions have been proposed, including a system where a user of the VoIP endpoint is expected to register the address associated with the VoIP endpoint (a so-called “emergency address”) which is stored in a memory and is retrieved when the user places an emergency call using the VoIP endpoint. The retrieved emergency address is used for two purposes: (i) to determine a Public Safety Answering Point (PSAP) that is responsible for handling calls from a particular geographic area associated with the emergency address; and (ii) transmit the emergency address to the PSAP to enable delivery of so-called “enhanced 9-1-1” services.
This solution has definite merit; however it still suffers a disadvantage associated with the fact that, due to the very nature of VoIP systems, the user can plug his or her VoIP endpoint (i.e., the VoIP phone, the ATA or the soft phone) anywhere where a high speed connection is available and place the emergency call. If the user has indeed moved his or her VoIP endpoint without updating the emergency address stored in the aforementioned memory with the new emergency address, the prior art system has no means of determining that the emergency address stored in the aforementioned memory is no longer the correct address associated with the location of the VoIP endpoint. Quite on the contrary, the aforementioned system will retrieve the stored address, determine the PSAP to route the emergency call to based on the retrieved emergency address and transmit the emergency address to the PSAP. It is clear that in this scenario, the call will most probably be routed to a wrong PSAP and the wrong emergency address information will be transmitted to the wrong PSAP. If the user of the VoIP endpoint is unable to speak (for example due to a medical condition the user is experiencing), an emergency response team will be dispatched to the wrong location, potentially resulting in a lethal outcome of the emergency situation experienced by the user.
Clearly, there is a need in the art for an improved system for verifying validity of the stored emergency address or other types of location information.